Signs of adaptation to local pH conditions across an environmental mosaic in the California Current Ecosystem

Little is known about the potential for rapid evolution in natural populations in response to the high rate of contemporary climatic change. Organisms that have evolved in environments that experience high variability across space and time are of particular interest as they may harbor genetic variation that can facilitate evolutionary response to changing conditions. Here we review what is known about genetic capacity for adaptation in the purple sea urchin, Strongylocentrotus purpuratus, a species that has evolved in the upwelling ecosystem of the Northeast Pacific Ocean. We also present new results testing for adaptation to local pH conditions in six populations from Oregon to southern California. We integrate data on 19,493 genetic polymorphisms with data on local pH conditions. We find correlations between allele frequency and rank average time spent at pH <7.8 in 318 single-nucleotide polymorphisms in 275 genes. Two of the genes most correlated with local pH are a protein associated with the cytoskeleton and a proton pump, with functional roles in maintenance of cell volume and with internal regulation of pH, respectively. Across all loci tested, high correlations with local pH were concentrated in genes related to transport of ions, biomineralization, lipid metabolism, and cell-cell adhesion, functional pathways important for maintaining homeostasis at low pH. We identify a set of seven genes as top candidates for rapid evolutionary response to acidification of the ocean. In these genes, the putative low-pH-adapted allele, based on allele frequencies in natural populations, rapidly increases in frequency in purple sea urchin larvae raised at low pH. We also found that populations from localities with high pH show a greater change in allele frequency toward putative low-pH-adapted alleles under experimental acidification, compared with low-pH populations, suggesting that both natural and artificial selection favor the same alleles for response to low pH. These results illustrate that purple sea urchins may be adapted to local pH and suggest that this species may possess the genetic capacity for rapid evolution in response to acidification. This adaptive capacity likely comes from standing genetic variation maintained in nature by balancing selection across the spatial and temporal environmental mosaic that characterizes the California Current Ecosystem.

Clinical characteristics of cough mixture abusers referred to three substance abuse clinics in Hong Kong: a retrospective study

OBJECTIVES. Cough mixture is the third most commonly abused substance in patients attending the Prince of Wales Hospital Substance Abuse Clinic. The content of the local cough mixture is not well researched. Paranoid psychosis manifesting as persecutory delusions and derogatory hallucination, as well as mood symptoms, is common in these patients. The natural history and outcome of such psychoses associated with cough mixture abuse are not well known. This study aimed to address these questions. METHODS. This was a retrospective study of cough mixture abuse in Hong Kong. Case records of cough mixture abusers currently receiving treatment at the 3 substance abuse clinics at the Prince of Wales Hospital, Alice Ho Miu Ling Nethersole Hospital, and the North District Hospital were retrieved for data collection. The patients' demographic data, duration and intake pattern of cough mixture, and use of any other drugs were documented. The presenting psychopathology, first urine toxicology results, diagnosis, treatment, number of hospitalizations, and course of the illness were also recorded. RESULTS. A total of 63 patients with the diagnosis of cough mixture abuse were identified in the database; 89% were male. The mean +/- SD age of the patients was 34.4 +/- 6.2 years; 67% were single and 83% were unemployed. The mean +/- SD age of onset of cough mixture abuse was 20 +/- 5 years. Psychiatric symptoms developed a mean +/- SD of 7.6 +/- 6.0 years after onset of abuse. According to the ICD-10 Mental and Behavioural Disorders criteria, the top psychiatric diagnoses were substance-induced psychotic disorder (67%), schizophrenia (19%), depressive disorder (11%), and dysthymia (10%). The most common ingredients in the urine sample at first presentation were promethazine (75%), pseudoephedrine (67%), codeine (60%), ephedrine (57%), zopiclone (17%), and hydrocodone (16%). Additionally, 16% of patients were in the priority follow-up group. The mean +/- SD follow-up period was 6.2 +/- 7.1 years during which there were 3.2 +/- 3.7 episodes of hospitalizations, with a mean +/- SD length of stay in each admission of 25.0 +/- 40.9 days. CONCLUSIONS. Promethazine, ephedrine, pseudoephedrine, codeine, and hydrocodone are the most common ingredients of cough mixture abused in this locality. Psychotic disorders are the most frequent psychiatric diagnosis associated with cough mixture abuse.

Successful nanolitre real-time PCR detection of respiratory pathogens in clinical specimens

We performed a proof-of-concept study to determine if human pathogens could be detected in clinical specimens using nanolitre-volume real-time PCR. Nanolitre PCR for Bordetella pertussis/B. parapertussis and respiratory syncytial virus (RSV) was performed on nasopharyngeal specimens and results compared with conventional methods. B. pertussis/B. parapertussis nanolitre PCR detection was 100% sensitive (20/20; 95% CI, 84-100%) and 100% specific (26/26; 95% CI, 87-100%). RSV nanolitre PCR was also 100% sensitive (21/21; 95% CI, 85-100%) and specific (25/25; 95%, CI 87-100%). Respiratory pathogens can be successfully detected in clinical specimens using nanolitre-volume PCR.

Persistency of Pseudomonas aeruginosa in sputum cultures and clinical outcomes in adult patients with cystic fibrosis

Our objective was to describe the natural history of infection with transmissible and unique strains of P. aeruginosa (PA) in adult CF patients and to determine if clearance of PA from sputum was associated with an improvement in clinical status. This was a 3-year prospective cohort study of adult patients with CF. Sputum was collected at baseline and annually. Rate of decline of FEV1, BMI, exacerbation rate, and time to death or transplant were compared between patients who cleared PA versus those in whom PA was persistent. A total of 373 patients were included in the study, 75% were infected with PA at baseline; 24% were infected with transmissible strains and 51% with unique strains. Patients infected with unique strains were more likely to clear PA from their sputum over 3 years compared to those infected with transmissible strains (19% vs 10%, P=0.05). Declines in FEV1 and rates of pulmonary exacerbations, deaths, or lung transplants were not different between patients who cleared PA compared to those who remained persistently infected. No clinical benefit was identified in patients who cleared PA from sputum compared to those who remained persistently infected.

Early maternal and paternal bonding, childhood physical abuse and adult psychopathic personality

BACKGROUND

A significant gap in the literature on risk factors for psychopathy is the relative lack of research on parental bonding.MethodThis study examines the cross-sectional relationship between maternal and paternal bonding, childhood physical abuse and psychopathic personality at age 28 years in a community sample of 333 males and females. It also assesses prospectively whether children separated from their parents in the first 3 years of life are more likely to have a psychopathic-like personality 25 years later.

RESULTS

Hierarchical regression analyses indicated that: (1) poor parental bonding (lack of maternal care and low paternal overprotection) and childhood physical abuse were both associated with a psychopathic personality; (2) parental bonding was significantly associated with psychopathic personality after taking into account sex, social adversity, ethnicity and abuse; (3) those separated from parents in the first 3 years of life were particularly characterized by low parental bonding and a psychopathic personality in adulthood; and (4) the deviant behavior factor of psychopathy was more related to lack of maternal care whereas the emotional detachment factor was related to both lack of maternal care and paternal overprotection.

CONCLUSIONS

Findings draw attention to the importance of different components of early bonding in relation to adult psychopathy, and may have potential implications for early intervention and prevention of psychopathy.

Predictors of life satisfaction in individuals with intellectual disabilities

BACKGROUND

The purpose of this study was to examine factors that predict life satisfaction in individuals with intellectual disabilities (ID). Two groups of variables were studied: life skills (interpersonal, instrumental and leisure) and higher-order predictors (social support, self-determination and productivity).

METHOD

Fifty-six participants with ID were recruited from two community agencies in Wisconsin. Data were collected using both a self-report inventory, which was administered to each individual in an interview format, and a behaviour rating scale, which was completed by a knowledgeable staff member. Hierarchical regression was used to analyse the data.

RESULTS

Both sets of variables were found to explain a significant amount of the variance in life satisfaction. Within the sets, social support and interpersonal skills were individually significantly associated with life satisfaction.

CONCLUSION

It is hoped that the results of this study will help support providers organise services in such a way that maximises the life satisfaction of the consumers that they serve.

Evaluation of the novel mitotic modulator ON 01910.Na in pancreatic cancer and preclinical development of an ex vivo predictive assay

The pupose of this study was to evaluate the activity of ON 01910.Na, a mitotic inhibitor, in in vitro and in vivo models of pancreatic cancer and to discover biomarkers predictive of efficacy. Successive in vitro and in vivo models were used; these included cell line-derived and patient-derived tumors from our PancXenoBank, a live collection of freshly generated pancreatic cancer xenografts. ON 01910.Na showed equivalent activity to gemcitabine against pancreatic cancer cell lines in vitro. The activity of the agent correlated with suppression of phospho-CDC25C and cyclin B1. These markers were optimized for a fine-needle aspirate ex vivo rapid assay. Cyclin B1 mRNA evaluation yielded the most optimal combination of accuracy and reproducibility. Next, nine patient-derived tumors from the PancXenoBank were profiled using the assay developed in cell lines and treated with ON01910.Na for 28 days. Two cases were cataloged as potential responders and seven as resistants. There was a correlation between the ex vivo assay and sensitivity to the tested agent, as the two cases prospectively identified as sensitive met prespecified criteria for response. Of the seven tumors of predictive resistant, only one was found to be sensitive to ON 01910.Na. In addition, there was a good correlation between cyclin B1 downregulation ex vivo and changes in cyclin B1 protein post-treatment. The novel mitotic inhibitor, ON 01910.Na, showed activity in preclinical model of pancreatic cancer. A rapid assay was rationally developed that not only identified cases sensitive to ON 01910.Na, but also anticipated the pharmacodynamic events occurring after in vivo exposure.

An open-label study of citalopram for major depression following traumatic brain injury

Major depression is associated with substantial psychosocial dysfunction and post-concussive symptomatology following traumatic brain injury (TBI). Studies to date of anti-depressant treatment for major depression post-TBI have been limited by small sample size. The goal of the present study is to examine the rates of response and remission associated with citalopram treatment for major depression following traumatic brain injury. Subjects with major depression following mild-to moderate TBI were treated with open-label citalopram with a starting dose of 20 mg/day to a maximum of 50 mg/day for either 6 weeks (n = 54) or 10 weeks (n = 26). The Hamilton Depression Rating Scale (HAMD) was used to assess depression severity. Response was defined by a 50% reduction in HAMD score, and remission was defined by a HAMD score of < or =7. The mean HAMD at baseline and 6 weeks were 23.66 (SD 6.8) and 16.30 (SD 9.3), respectively (t[53] = 7.157, p < 0.0001). The mean HAMD at 10 weeks was 12.96 (SD 7.9) (t[25] = 7.323, p < 0.0001). At 6 weeks, 54 subjects were assessed and 27.7% responded with 24.1% in remission. At 10 weeks, 26 subjects were assessed and 46.2% responded with 26.9% in remission. The response rate in the present sample was substantially lower than previously reported for patients with TBI, but comparable to the results of the largest effectiveness trial of citalopram for general out-patients with major depression in the absence of TBI.

The role of endothelial dysfunction in the pathogenesis of impaired diabetic wound healing: a novel therapeutic target?

The global burden of diabetes is attributed to its multiple associated complications including impaired wound healing which can ultimately result in amputation. Peripheral vascular disease, infection, neuropathy and abnormal local cellular and cytokine activity are some of the traditionally cited pathological instigators of defective diabetic wound repair. Despite intensive research and subsequent advances in diabetic wound care technology a single treatment with measurable clinical impact has yet to be determined. The phenomenon of endothelial dysfunction as seen in atherosclerosis and recently identified as a characteristic of diabetic vasculature may contribute to impaired cutaneous healing in this group. Indicators of endothelial dysfunction have been demonstrated in diabetic wounds by a number of investigators. Successful results are being obtained with modifiers of endothelial function in the management of cardiovascular disease. We hypothesise that endothelial dysfunction plays a substantial contributory role in the pathogenesis of wound healing impairment of diabetes and holds potential as a target for therapeutic intervention.

KCC3 and KCC4 expression in rat adult forebrain

Potassium chloride ion cotransporters (KCCs) are part of a family of transporters classically described as being involved in cell volume regulation. Recently, KCC2 has been shown to have a role in the development of the inhibitory actions of amine transmitters, whereas KCC3 also plays a fundamental role in the development and function of the central and peripheral nervous system. We have re-assessed the expression of each of the known KCCs in the rat forebrain using RT-PCR and in situ hybridisation histochemistry. As well as confirming the widespread expression of KCC1 and KCC2 throughout the brain, we now show a more restricted expression of KCC3a in the hippocampus, choroid plexus and piriform cortex, as well as KCC4 in the choroid plexus and the suprachiasmatic nucleus of the hypothalamus. The expression of KCC4 in the latter and KCC2 in the lateral hypothalamic and ventromedial hypothalamic nuclei suggests that these cotransporters may have selective roles in neuroendocrine or homeostatic functions. Finally, we demonstrate the existence of a truncated splice variation of KCC3a in the rat that appears to be expressed exclusively in neurons (as is KCC2), whereas the native form of KCC3a and KCC4 appears to be expressed in glial cells.

Performance of bioprostheses and mechanical prostheses assessed by composites of valve-related complications to 15 years after aortic valve replacement

OBJECTIVE

This study was conducted to compare the composites of valve-related complications, namely reoperation, morbidity (defined as permanent neurologic or other functional impairment), and mortality, between bioprostheses and mechanical prostheses for aortic valve replacement.

METHODS

Between 1982 and 1998, 2195 bioprostheses were implanted in 2179 patients and 980 mechanical prostheses were implanted in 883 patients. Total follow-up was 16,442 years and 5740 years for bioprostheses and mechanical prostheses, respectively. Eight variables were considered as predictors of risk for the composites of valve-related complications.

RESULTS

Linearized rates for valve-related reoperation were 1.3%/patient-year and 0.3%/patient-year for bioprostheses and mechanical prostheses (P < .001), respectively. All age groups were differentiated, except >70 years. Valve-related morbidity was differentiated for all age groups and overall, for bioprostheses and mechanical protheses, was 0.4 %/patient-year and 2.1%/patient-year, respectively (P < .001). Overall valve-related mortality was 1.0%/patient-year for bioprostheses and 0.7%/patient-year for mechanical prostheses (P = .018). Age and valve-type were predictive risk factors for reoperation and morbidity, whereas age alone was predictive of mortality. Actual freedom from valve-related reoperation favored mechanical prostheses for all age groups, except 61-70 years and >70 years. Actual freedom from valve-related morbidity favored bioprostheses in all age groups, except < or =40 years. Actual freedom from valve-related mortality was undifferentiated in patients 51-60, 61-70, and >70 years.

CONCLUSION

No differences were observed in valve-related reoperation and mortality in patients >60 years. Comparative evaluation gives high priority for bioprostheses in patients >60 years based on improved morbidity profile. This evaluation extends this center's recommendation for bioprostheses in aortic valve replacement to include patients >60 years.

Valve Replacement Surgery Complicated by Acute Renal Failure-Predictors of Early Mortality

BACKGROUND

Acute renal failure (ARF) is a serious complication of valve replacement surgery. The aim of this study was to determine the predictors of early mortality and if causative factors are preventable.

METHODS

In the 25-year period between 1977 and 2002, 255 (2.6%) of 9721 patients (11,007 operations), who had valve replacement surgery, were managed for ARF with dialysis. The mean age of the patient population was 67.1 +/- 11.6 years (range 24 to 87 years, median 70.3 years). Fifty preoperative, operative, and postoperative risk factors were assessed as predictors of early mortality by univariate and multivariate modeling.

RESULTS

The early mortality was 25.1% (64 patients). The predictors by univariate analysis were: New York Heart Association class (p = 0.001); ASA within 5 days (p = 0.030); cardiogenic shock (p = 0.010); infection--perioperative sepsis and preoperative endocarditis (p = 0.000); intraoperative stroke (p = 0.003); status--emergent (p = 0.000); mitral valve replacement (p = 0.040); ischemic (X-clamp) time >120 minutes (p = 0.020); cardiopulmonary bypass time >180 minutes (p = 0.000); surgical time >360 minutes (p = 0.000); surgical hemorrhage (p = 0.020); acute respiratory distress syndrome (ARDS) (p = 0.040). Multivariate predictors were urgent status of operation, odds ratio (OR) 0.3 (p = 0.029); emergent status of operation, OR 5.8 (p = 0.034); ischemic (X-clamp) time >120 minutes, OR 4.4 (p = 0.030); surgical time >360 minutes, OR 6.3 (p = 0.019); surgical hemorrhage, OR 5.1 (p = 0.003); perioperative nosocomial sepsis, OR 3.8 (p = 0.006); and preoperative endocarditis, OR 4.4 (p = 0.004).

CONCLUSIONS

Early mortality from ARF in valve replacement surgery is related to emergent status, ischemic and surgical times, surgical hemorrhage, and nosocomial infection/preoperative endocarditis. Among the variables assessed, preoperative renal insufficiency, unstable angina/recent myocardial infarction <6 weeks, and concomitant coronary artery bypass were not predictive. The evaluation of predictors of ARF requires further extensive assessment.

Insulin resistance causes increased beta-cell mass but defective glucose-stimulated insulin secretion in a murine model of type 2 diabetes

AIMS/HYPOTHESIS

Although insulin resistance induces compensatory increases in beta cell mass and function to maintain normoglycaemia, it is not clear whether insulin resistance can precipitate beta cell dysfunction and hyperglycaemia without a pre-existing beta cell susceptibility. We therefore examined the beta cell phenotype in the MKR mouse, a model in which expression of a dominant-negative IGF 1 receptor (IGF1R) in skeletal muscle leads to systemic insulin resistance and diabetes.

MATERIALS AND METHODS

Circulating glucose, insulin and glucagon concentrations were measured. Insulin sensitivity, glucose tolerance and insulin release in vivo were assessed by i.p. insulin and glucose tolerance tests. Beta cell function was assessed via insulin secretion from isolated islets and the glucose gradient in the perfused pancreas. Beta cell morphology was examined via immunohistochemistry. MKR mice were fed a high-fat diet containing sucrose (HFSD) to test metabolic capacity and beta cell function.

RESULTS

Insulin-resistant MKR mice developed hyperglycaemia and a loss of insulin responsiveness in vivo. Basal insulin secretion from the perfused pancreas was elevated, with no response to glucose. Despite the demand on insulin secretion, MKR mice had increased pancreatic insulin content and beta cell mass mediated through hyperplasia and hypertrophy. The HFSD worsened hyperglycaemia in MKR mice but, despite increased food intake in these mice, failed to induce the obesity observed in wild-type mice.

CONCLUSIONS/INTERPRETATION

Our studies demonstrate that insulin resistance of sufficient severity can impair glucose-stimulated insulin secretion, thereby undermining beta cell compensation and leading to hyperglycaemia. Moreover, because insulin stores were intact, the secretory defects reflect an early stage of beta cell dysfunction.